NASA pilots and flight engineers, together with colleagues from the National Oceanic and Atmospheric Administration (NOAA), have successfully completed the first science flight of the Global Hawk aircraft over the Pacific Ocean. The Global Hawk is a robotic plane that can fly autonomously to altitudes above 60,000 feet (18.3 kilometers) -- roughly twice as high as a commercial airliner -- and as far as 11,000 nautical miles (20,000 kilometers) -- half the circumference of Earth. GloPac researchers will directly measure and sample greenhouse gases, ozone-depleting substances, aerosols, and constituents of air quality in the upper troposphere and lower stratosphere.